Vitamin D deficiency and calcium intake in reference to increased body mass index in children and adolescents

Clinical Characteristics and Outcomes of Limb Fractures in Saudi Children

BACKGROUND

 Children's bones are at high risk of fracture as they grow. The clinical characteristics of fractures in children differ from those in adults. Studying fractures in healthy children is critical for identifying cases of fragility fractures. The aim of this study was to assess the clinical characteristics of limb fractures as well as clinical indicators of fracture healing outcomes in healthy Saudi children seen in an emergency room.

METHODS

A retrospective review of the treatment course of all pediatric fractures and related factors treated at King Abdullah Specialist Children's Hospital (KASCH) in Riyadh between 2016 and 2018 was conducted. Children with a primary bone disorder or chronic comorbidities known to affect bone health were excluded.

RESULTS

 The study included 143 patients (mean age ± SD = 8.23 + 3.76 years), and 71% (n = 102) were males. Motor vehicle accidents (MVAs) were the most common mechanism of injury, accounting for 50 (35%) cases, followed by fall injuries, sports injuries, and pedestrian accidents at 45 (31.4%), 16 (11.2%), and 13 (9.1%), respectively. A total of 178 fractures were reported, with the femur (n = 75, 42.1%) being the most common of the reported fracture sites, followed by the forearm (n = 44, 24.7%). The most common type of fracture was transverse fracture (n = 96, 54% of patients). Vitamin D levels were measured in 53/143 cases. Of these, vitamin D deficiency was found in 38 (71.7%) patients. The average time for fracture healing was 32.9 ± 30.2 weeks. The mechanisms of injury, including MVAs and sports injuries, as well as femur and forearm fractures, were clinical factors that were independently associated with a longer duration of fracture healing time (p < 0.001), but age, gender, and vitamin D status were not associated with that outcome.

CONCLUSION

 MVAs and fall injuries were the most common causes of fracture in our patients. MVAs and sports injuries were associated with prolonged healing time. Large prospective, multicenter, or field studies may be required to further explore clinical characteristics, outcomes, and environmental factors.

Nutritional status of school-age children and adolescents in low- and middle-income countries across seven global regions: a synthesis of scoping reviews

OBJECTIVE

To summarise available evidence on the nutritional status of school-age children and adolescents (5-19 years) from seven global regions and on interventions implemented to improve malnutrition in this population.

SETTING

Global.

DESIGN

Findings were compiled from seven scoping literature reviews, including data from low- and middle-income countries within the following UNICEF-defined global regions: East Asia and Pacific; Europe and Central Asia; South Asia; West and Central Africa; Eastern and Southern Africa; Middle East and North Africa and Latin America and the Caribbean.

RESULTS

A double burden of malnutrition was evident across the world regions reviewed: stunting, thinness, anaemia and other micronutrient deficiencies persisted, alongside rising overweight and obesity prevalence. Transitions towards diets increasingly high in energy-dense, processed and micronutrient-poor foods were observed. Evidence from intervention studies was limited, but suggested that providing multiple micronutrient-fortified foods or beverages at school may effectively target micronutrient deficiencies and facilitate weight gain in undernourished populations. Interventions to prevent or manage overweight and obesity were even more limited. There was minimal evidence of using novel technological approaches to engage school-age children and adolescents, or of involving them in designing interventions.

CONCLUSION

The limited data available on nutrition of school-age children and adolescents are neither standardised nor comparable. Consensus on methods for assessing nutritional status and its determinants for this age group is urgently needed to set targets and monitor progress. Additionally, strategies are required to ensure that nutritious, safe and sustainable diets are available, affordable and appealing.

Correlation of Gut Microbiota, Vitamin D Status, and Pulmonary Function Tests in Children With Cystic Fibrosis

Background

Children with cystic fibrosis (CF) are expected to have suboptimal serum vitamin D status and altered gut microbiota. The altered gut microbiota is hypothesized to have a pro-inflammatory effect that further complicates the existing respiratory inflammation. Emerging evidence suggests an association between vitamin D and gut microbiota. The aim of this study was to assess the relationships between 25-hydroxyvitamin D [25(OH)D] status, pulmonary function, and fecal bacteria in children with CF.

Methods

In this cross-sectional study, a total of 35 children with CF (8.7 ± 2.83 years) and 24 controls without CF (9 ± 2.7 years) were included in this study. Serum 25(OH)D status was measured using the Elecsys vitamin D total II assay. In the CF group, gut microbiota composition was assessed using real-time PCR analysis. Pulmonary function tests (PFTs) were measured using spirometry. Comparisons between the CF and non-CF controls were conducted using the independent sample t-test. In the CF group, one-way analysis of variance (ANOVA) was used to assess differences in PFTs and gut microbiota composition across the three vitamin D subgroups. The correlations between 25(OH)D status and PFTs, or gut microbiota composition, and PFTs with gut microbiota composition were analyzed using the Pearson's correlation coefficient test.

Results

Children with CF had significantly lower serum 25(OH)D levels compared with children without CF (44.3 ± 22.4 vs. 59 ± 25.5, respectively, P = 0.026). Children with CF with optimal serum 25(OH)D level had significantly higher levels of Bacteroidetes, Firmicutes, and total bacteria (P = 0.007, P = 0.007, and P = 0.022, respectively). The level of Firmicutes was found to be significantly higher in mild forced expiratory volume in 1 s (FEV1) compared with moderate FEV1 (P = 0.032), whereas the level of the other bacteria species was comparable across FEV1 severity groups.

Conclusion

Our findings may encourage studies that target and modify gut microbiota to potentially achieve better outcomes in terms of respiratory function in CF.

Impact of Obesity on Bone Metabolism in Children

Obesity is an epidemic disease that can increase the incidence of type 2 diabetes, cardiovascular disease, malignancy, hypertension, and other health problems that affect the musculoskeletal system. There is a complex interaction between obesity and bone metabolism. In children with obesity, the peroxisome proliferator-activated receptor gamma pathway causes the differentiation of mesenchymal stem cells into adipocytes via osteoblasts, in which results in low bone mass and osteoporosis. Systemic inflammation in obesity has negative effects on bone metabolism. An increase in the number and size of adipose tissue and adipocytokines secreted from adipocytes affect the bone mass of the whole body with hormonal and biochemical effects. The skeletal effects of obesity are mediated by higher oxidative stress and increased production of proinflammatory cytokines. Osteoporosis due to obesity has increased morbidity and mortality in recent years, resulting in important health problems in developed and developing countries.

Nutrient intake and gender differences among Saudi children

Dietary surveillance is necessary to determine community needs for nutrition interventions. Yet, the nutrient intake of Saudi children has not been previously investigated. The objective of the present study is to evaluate dietary data of Saudi children and investigate gender differences in nutrient intake. In this cross-sectional study, dietary data of 424 Saudi children (6–12 years of age) were collected using telephone-administered single 24-h dietary recall. Three 24-h dietary recalls were collected from a subsample of 168 children (39⋅6 %) and compared with the Dietary Recommended Intakes (DRIs). Nutrient intakes and proportions of children meeting the DRI requirements were similar and did not vary by children's gender. Over two-thirds of the children had an adequate usual intake of vitamin B12, and over half had adequate intakes (AIs) of vitamin C and phosphorus. On the other hand, our data indicated that low proportions of children consumed adequate usual intakes of magnesium and vitamin E. Over half of the children in our sample met the AI for sodium and vitamin D. Only small proportions of children met the AI for calcium, potassium and fibre. Cholesterol and saturated fat intake exceeded the limits of 300 mg and 10 % of total energy intake by 13⋅7 % (n 23) and 80⋅4 % (n 135) of the sample, respectively. Suboptimal intake of several micronutrients was observed among children, suggesting an urgent need to identify barriers to high-quality diet and to develop evidence-based interventions to promote optimal dietary efficacy for children in Saudi Arabia.

Vitamin D status and its dietary and lifestyle factors in children during the first 5 years of life: A cross-sectional multicentre Jiangsu bone study

BACKGROUND

To explore the vitamin D status with its demographic and lifestyle factors including dietary, supplementation, and physical activity in 0-5 years old children.

METHODS

This was a large population-based cross-sectional multicentre study in which the children were recruited from 12 Children's Health Care Centers by a stratified cluster random-sampling method in 10 cities in Jiangsu Province, China.

RESULTS

A total number of 5289 children were investigated. The prevalence of vitamin D deficiency was 30.1%. The concentration of 25 hydroxyvitamin D was 64.0 (46.3-83.0) nmol mL^-1 after adjustment for covariates. Children with higher risk of vitamin D deficiency were more likely to be at older age, girls, survey conducted in spring, location in southern Jiangsu province, residence in urban, outdoor activity < 2 h day^-1 (all p < 0.05). Moreover, those with lower risk were more likely to be the number of parity ≥ 2 times, vitamin D supplementation from birth to 6 months, the initial time of vitamin D supplementation after birth ≤ 1 months, vitamin D and calcium supplementation in the last 3 months, and dose of vitamin D supplementation > 400 IU day^-1 (all p < 0.05). Children with preferences for sweets, meat consumption > 150.0 g day^-1 , milk consumption < 250 mL day^-1 , time of sleeping < 10 h day^-1 had higher risks of vitamin D deficiency. However, these relationships were affected by demographics.

CONCLUSIONS

Vitamin D status during the first five years of life was suboptimal and was associated with demographic and lifestyle determinants including milk, meat, sweets, vitamin D and calcium supplementation, sleeping and outdoor activity.

Prevalence and predictors of vitamin D deficiency in a nationally representative sample of Australian adolescents and young adults

Background/Objectives

Vitamin D deficiency is a public health concern worldwide. Maintaining vitamin D sufficiency during growth periods is essential. We aimed to determine the prevalence and predictors of vitamin D deficiency in Australian adolescents and young adults.

Subject/Methods

We used data from adolescents (12–17 years, n = 692) and young adults (18–24 years, n = 400) who participated in the nationally representative 2011–2013 Australian Health Survey. Serum 25-hydroxyvitamin D concentrations were measured using a method certified to international standards, with prevalence reported for <50 (vitamin D deficiency), 50–<75, ≥75 and >125 nmol/L. Independent predictors of vitamin D deficiency were determined using a survey-weighted Poisson regression model.

Results

Overall, 17% of adolescents and 32% of young adults were vitamin D deficient. In models adjusted for sex, age, region of birth, socioeconomic status, BMI and season (and education, smoking status and physical activity in young adults only), the prevalence ratio (PR) for vitamin D deficiency was more than double in participants born outside Australia (adolescents: PR 2.46; 95% confidence interval (CI) = 1.59, 3.81; young adults: PR 2.12; 95% CI = 1.46, 3.07), and also varied by season (adolescents: spring vs summer PR 2.47; 95% CI = 1.22, 5.01 and winter vs summer PR 2.01; 95% CI = 1.03, 3.92; young adults: winter vs summer; PR 3.32; 95% CI = 1.69, 6.53). Other predictors of vitamin D deficiency were overweight compared with healthy weight (adolescents) and lower physical activity (young adults).

Conclusions

Strategies based on safe sun exposure and dietary approaches are needed to achieve and maintain adequate vitamin D status, particularly in young adults.

Inflammatory and Adipokine Status from Early to Midpregnancy in Arab Women and Its Associations with Gestational Diabetes Mellitus

Objective

To examine differences in maternal serum levels of adipokines (adiponectin, leptin, and resistin) and inflammatory markers (tumor necrosis factor-alpha (TNF-α) and interlukin-6 (IL-6)) from early to midpregnancy among Arab women with or without gestational diabetes mellitus (GDM), along with their links to GDM risk.

Methods

This is a multicenter prospective study involving 232 Saudi women attending obstetric care. Both circulating adipokine and markers of inflammation were observed at the first (eight to 12 weeks) and second trimesters (24 to 28 weeks). GDM was screened at 24 to 28 weeks using the International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criteria.

Results

Age and body mass index- (BMI-) matched circulating TNF-α was significantly higher in women with GDM in comparison to non-GDM women (p = 0.01). Adiponectin and resistin significantly decreased from the first to second trimester in women without GDM (p = 0.002 and 0.026, respectively). Leptin presented a significant rise from the first to second trimester in both groups, with a higher increase in women with GDM (p = 0.013). Multivariate logistic regression analysis revealed that TNF-α was significantly correlated with GDM (p = 0.03). However, significance was lost after adjustments for maternal and lifestyle risk factors (OR 23.58 (0.50 to 1119.98), p = 0.11).

Conclusion

Inflammatory and adipocytokine profiles are altered in Arab women with GDM, TNF-α in particular. Further studies are needed to establish whether maternal inflammatory and adipocytokine profile influence fetal levels in the same manner.

Prevalence and social determinants of overweight and obesity in adolescents in Saudi Arabia: A systematic review

Obesity in adolescents has a serious impact later in life in the form of disturbances in health and wellbeing. We aimed to evaluate the prevalence of overweight and obesity (Ow/Ob) in Saudi adolescents and to construct an ecological model of social determinants (SDs) of Ow/Ob and evaluate current evidence of their effect on Saudi adolescents. A systematic review of literature reported up until 31 December 2018 on Ow/Ob and factors that can influence them in Saudi adolescents was conducted. Fifty-one studies with n = 97 666 adolescents (55.6% males) were reviewed. The prevalence of Ow/Ob started off high and continued to increase over time. Most of the 49 reviewed SDs reports, from 19 studies, showed positive association between SDs constructed ecological model and Ow/Ob in Saudi adolescents. The prevalence of Ow/Ob among adolescents is a major public health problem in Saudi Arabia, is growing at an alarming rate and SDs play a significant role in this problem, and should be considered in all strategies targeting it. The constructed ecological model for SDs of Ow/Ob in adolescents can serve as a useful exploratory tool that helps investigating the multi-faceted aetiology of adolescent Ow/Ob and facilitates the development of effective intervention and prevention programmes.

Vitamin D, melanoma risk, and tumor thickness in PLCO cancer screening trial patients

OBJECTIVE

The incidence of melanoma is increasing. Other than limiting UV exposure, few factors prevent or reduce the risk of melanoma. The aim of this study is to evaluate the relationship between vitamin D intake and melanoma risk in the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial.

METHODS

A secondary data analysis was performed on PLCO data. More than 1,300 participants developed melanoma.

RESULTS

Melanoma risk may be increased among men within the highest quartile of vitamin D intake (HR 1.27, 95% CI 0.99, 1.61). Women in the highest quartile of vitamin D intake had a decreased risk of invasive melanoma (HR 0.63, 95% CI 0.41, 0.96). Higher education and being white corresponded with deeper tumors (P < .001).

CONCLUSION

High reported vitamin D intake resulted in an increased risk of melanoma among men. Vitamin D intake yielded a protective effect against invasive melanoma in women.

Food Consumption Patterns and Nutrient Intakes of Children and Adolescents in the Eastern Mediterranean Region: A Call for Policy Action

The Eastern Mediterranean Region (EMR) has witnessed significant social and economic changes that may have influenced the diet of children and adolescents, and increased the risk for obesity and malnutrition in this age group. This review aims to characterize and assess food consumption patterns and nutrient intakes amongst school-aged children (5-10 years) and adolescents (10-19 years) in countries of the EMR. Electronic databases (MedLine, PubMed, Scopus, and Google Scholar) were searched for relevant articles published between 2005 and 2020; international organizations and governmental websites were also searched. Available studies documented low intakes of fruits, vegetables and fiber, inadequate consumption of water, milk and dairy products, coupled with high intakes of fat, saturated fat, and sugar sweetened beverages, as well as a frequent consumption of energy-dense, nutrient poor foods such as sweet and savory snacks. Micronutrient inadequacies were also observed, particularly for calcium, iron, zinc and vitamins A, D, C, and folate. Acknowledging the impact that nutrition may have on building societies and transforming the lives of children, adolescents and their families, there is a crucial need for a food system approach in developing and implementing national and regional policies and interventions aimed at improving the diet of children and adolescents.

Response of Vitamin D after Magnesium Intervention in a Postmenopausal Population from the Province of Granada, Spain

Menopause is a stage of hormonal imbalance in women which, in addition to other physiopathological consequences, poses a risk of deficiency of key micronutrients such as magnesium and vitamin D. A study was made of the influence of a magnesium intervention upon vitamin D status in a postmenopausal population from the province of Granada (Spain). Fifty-two healthy postmenopausal women between 44–76 years of age were included. Two randomized groups—placebo and magnesium (500 mg/day)—were treated during eight weeks. Nutrient intake was assessed using questionnaires based on 72-h recall. Vitamin D was analyzed by liquid chromatography—tandem mass spectrometry. Baseline vitamin D proved deficient in over 80% of the subjects. The administration of magnesium resulted in significantly increased vitamin D levels in the intervention group versus the controls (p < 0.05). Magnesium supplementation improved vitamin D status in the studied postmenopausal women.

Anti-Obesity Effects of Dietary Calcium: The Evidence and Possible Mechanisms

Obesity is a serious health challenge worldwide and is associated with various comorbidities, including dyslipidemia, type 2 diabetes, and cardiovascular disease. Developing effective strategies to prevent obesity is therefore of paramount importance. One potential strategy to reduce obesity is to consume calcium, which has been implicated to be involved in reducing body weight/fat. In this review, we compile the evidence for the anti-obesity roles of calcium in cells, animals, and humans. In addition, we summarize the possible anti-obesity mechanisms of calcium, including regulation of (a) adipogenesis, (b) fat metabolism, (c) adipocyte (precursor) proliferation and apoptosis, (d) thermogenesis, (e) fat absorption and excretion, and (f) gut microbiota. Although the exact anti-obesity roles of calcium in different subjects and how calcium induces the proposed anti-obesity mechanisms need to be further investigated, the current evidence demonstrates the anti-obesity effects of calcium and suggests the potential application of dietary calcium for prevention of obesity.

Nutritional status and dietary intakes of children amid the nutrition transition: the case of the Eastern Mediterranean Region

The Eastern Mediterranean Region (EMR) is undergoing social and economic changes that may impact the nutritional status of children living in its countries. The objective of this review is to evaluate the nutritional status and dietary intakes of children (0-12 years) in selected EMR countries, namely, Jordan, Lebanon, Kingdom of Saudi Arabia (KSA), and the United Arab Emirates. MedLine, PubMed, Scopus, and Google Scholar were searched for relevant articles published between 1990 and 2016; international organizations and governmental websites were also searched. Stunting in the region was estimated at 7.3% to 9.3%, wasting at 1.1% to 11.8%, and underweight at 1.6% to 5.3%. In contrast, overweight and obesity affected 19% to 21% of school-aged children from Lebanon and KSA. Available biochemical data showed that pediatric anemia, vitamin A, and vitamin D deficiencies remain a challenge in the region. Dietary intake studies have identified inadequate intakes of iron, calcium, zinc, folic acid, vitamin A, and vitamin D, concurrently with high intakes of fat, saturated fat, and sugar. This review provides valuable insight into the nutrition situation of children in 2 major areas of the EMR, the Levant and the Gulf, and identified several gaps and challenges in existing nutritional assessment studies. Key issues include the triple burden of malnutrition in this age group (underweight, nutrient inadequacies, and overweight/obesity), while calling for integrated action to improve the nutritional status of children in countries of the region. Opportunities for future research include nationwide nutritional and dietary surveys in countries where the largest data gaps remain such as the United Arab Emirates and KSA.

Vitamin D Deficiency Prevalence and Predictors in Early Pregnancy among Arab Women

Data regarding the prevalence and predictors of vitamin D deficiency during early pregnancy are limited. This study aims to fill this gap. A total of 578 Saudi women in their 1^st trimester of pregnancy were recruited between January 2014 and December 2015 from three tertiary care antenatal clinics in Riyadh, Saudi Arabia. Information collected includes socio-economic, anthropometric, and biochemical data, including serum vitamin D (25(OH)D) levels, intake of calcium and vitamin D, physical activity, and sun exposure indices. Pregnant women with 25(OH)D levels <50 nmol/L were considered vitamin D deficient. The majority of participants (n = 468 (81%)) were vitamin D deficient. High levels of indoor activity, whole body clothing, multiparity, total cholesterol/HDL ratio(>3.5), low HDL-cholesterol, and living in West Riyadh were significant independent predictors for vitamin D deficiency, with odds ratios (ORs) (95% confidence interval) of 25.4 (5.5–117.3), 17.8 (2.3–138.5), 4.0 (1.7–9.5), 3.3 (1.4–7.9), 2.8 (1.2–6.4), and 2.0 (1.1–3.5), respectively. Factors like increased physical activity, sun exposure at noon, sunrise or sunset, high educational status, and residence in North Riyadh were protective against vitamin D deficiency with ORs 0.2 (0.1–0.5); 0.2 (0.1–0.6); 0.3 (0.1–0.9); and 0.4 (0.2–0.8), respectively. All ORs were adjusted for age, BMI, sun exposure, parity, summer season, vitamin D intake, multivitamin intake, physical activity, education, employment, living in the north, and coverage with clothing. In conclusion, the prevalence of vitamin D deficiency among Saudi women during early pregnancy was high (81%). Timely detection and appropriate supplementation with adequate amounts of vitamin D should reduce the risks of vitamin D deficiency and its complications during pregnancy.

Hypovitamininosis D in Childhood Cancer Survivors: Importance of Vitamin D Supplementation and Measurement Over Different Points of Time

This observational retrospective cross-sectional and case-controlled study measures levels of 25-hydroxy-vitamin D (25-OH-VD) in pediatric cancer survivors at different intervals and assesses the effect of 2 supplementation regimens over a period of 12 months. Sixty-eight patients were included in this quasi-experimental study, of which 32 were boys and 36 were girls. A control group of 30 healthy children were included. It was found that initial 25-OH-VD levels were insufficient (<30 ng/mL) in 61 patients (89.7%). Yet, no significant difference between the levels of 25-OH-VD in these patients as compared with the healthy control group was evidenced. However, 25-OH-VD levels were significantly higher at 18 months in patients who were supplemented with oral 50,000 IU/month vitamin D during the 12 months in comparison with patients supplemented with 1000 IU/day. Our findings indicate that pediatric cancer survivors who require frequent monitoring of their 25-OH-VD levels yielded better results when supplemented with higher doses of vitamin D over longer periods of time. A course of oral vitamin D supplementation regimen of 50,000 IU/month gave effective results with excellent compliance and no reports of any adverse or harmful effects.

Obesity is associated with vitamin D deficiency in Danish children and adolescents

BACKGROUND

Sufficient serum concentrations of vitamin D are required to maintain bone health during growth. The aims of this study were to determine whether vitamin D deficiency is more prevalent among children and adolescents with obesity compared to their normal weight peers and to identify clinical and biochemical variables associated with vitamin D deficiency.

METHODS

One thousand four hundred and eighty-four children and adolescents with overweight/obesity and 2143 population-based controls were recruited from the Danish Childhood Obesity Biobank. Anthropometric variables and fasting concentrations of serum 25-hydroxy vitamin D (25-OH-D), plasma parathyroid hormone (PTH), calcium and phosphate were assessed at baseline. Vitamin D deficiency was defined as serum 25-OH-D concentrations <30 nmol/L. Linear and logistic regressions were used to identify variables associated with vitamin D deficiency.

RESULTS

A total of 16.5% of the children and adolescents with obesity (body mass index [BMI] standard deviation score [SDS]>2.33) exhibited vitamin D deficiency, with an odds ratio (OR) 3.41 (confidence interval [CI]: 2.27-5.71; p<0.0001) for being vitamin D deficient compared to their normal weight peers. BMI-SDS was independently and inversely associated with serum 25-OH-D concentrations. Other independent risk factors for vitamin D deficiency were being older than 14 years (OR: 2.39; CI: 1.28-4.48; p=0.006), more than 4 daily hours of screen time (OR: 4.56; CI: 2.59-8.05; p<0.0001) and blood sample assessment during winter-spring (OR: 6.44; CI: 4.47-9.26; p<0.0001).

CONCLUSIONS

Vitamin D deficiency was common among Danish children and adolescents with obesity. The degree of obesity was independently associated with lower serum 25-OH-D concentrations.

Prevalence and predictors of hypovitaminosis D among the elderly in subtropical region

The prevalence of low vitamin D status in the elderly population of subtropical area and the potential risk/protective factors have not been addressed. This cross-sectional questionnaire-based study, which collected demographic/anthropometric data and information on diet habit and sun exposure, recruited 170 subjects with mean age 70.9±5.6 in rural areas of southern Taiwan. Serum 25-OH vitamin D, calcium, and intact parathyroid hormone were also measured. Using cut-off level of 30 ng/mL, subjects were divided into low (n = 95) and normal (n = 75) serum vitamin D groups. The results demonstrated a low vitamin D status in 30.6% of men and 57.7% of women. Dietary vitamin D intake was another factor associated with vitamin D status (p = 0.02). Logistic regression identified inadequate intake of vitamin D-rich food as the only risk factor for low vitamin D status in men (OR = 4.55, p = 0.01), whereas inadequate sun exposure was the only predictable risk with dose-response relationship in women (low vs. high sun exposure, OR = 6.84, p = 0.018; moderate vs. high sun exposure, OR = 6.67, p = 0.005). In conclusion, low vitamin D status was common in the elderly of subtropical rural areas. Low sun exposure and inadequate dietary vitamin D consumption were associated with a low vitamin D status in females and males, respectively.

Comparisons in childhood obesity and cardiometabolic risk factors among urban Saudi Arab adolescents in 2008 and 2013

BACKGROUND

We aimed to compare the prevalence of childhood obesity and other cardiometabolic risk factors from two independent cohorts (2008 and 2013) in Riyadh, Saudi Arabia.

METHODS

A total of 4549 adolescents aged 12-18 years [2454 boys, 2095 girls], taken from two independent cohorts, 5 years apart (2008 and 2013), were included. Anthropometrics were measured, and fasting blood samples were taken to ascertain glucose and lipid profile.

RESULTS

The overall prevalence of obesity was significantly higher in 2013 [15.3 (95% confidence interval 13.7-16.9)] than 2008 [12.6 (11.3-13.9)] (P = 0.012). Stratified by sex, the prevalence of obesity among boys was significantly higher in 2013 than 2008 [2008 = 12.0 (10.3-13.7) versus 2013 = 17.4 (15.1-19.7); P < 0.001]. The age groups 13 and 15 years had a significantly higher mean triglycerides in 2013 than 2008 (P-values 0.003 and <0.001, respectively) and lower mean HDL-cholesterol also in the 13 years old age group (P < 0.001).

CONCLUSIONS

The prevalence of childhood obesity in Saudi Arabia has increased in particular age groups (13-15 years) during a 5-year span. Special attention is warranted in these vulnerable age groups, particularly in boys, as cardiometabolic risk factors appear to worsen.

Nationality, Gender, Age, and Body Mass Index Influences on Vitamin D Concentration among Elderly Patients and Young Iraqi and Jordanian in Jordan

Vitamin D is necessary for maintaining and regulating calcium levels; thus, insufficiency of vitamin D increases the risk of many chronic diseases. This study aimed to examine vitamin D levels among Jordanian and Iraqi volunteers and find the relation between vitamin D level and lipid profile patients. Vitamin D levels were evaluated using enzyme-linked immunosorbent assay. For young healthy group subjects, vitamin D levels were 20.60 ± 5.94 ng/mL for Jordanian and 27.59 ± 7.74 ng/mL for Iraqi. Vitamin D concentrations for young males and females were 25.82 ± 8.33 ng/mL and 21.95 ± 6.39 ng/mL, respectively. Females wearing hijab were 20.87 ± 6.45 ng/mL, while uncovered females were 23.55 ± 6.04 ng/mL. For >40 years Iraqi subjects, vitamin D level for healthy was 29.78 ± 9.49 ng/mL and 23.88 ± 7.93 ng/mL for hyperlipidemic subjects. Vitamin D levels for overweight and obese healthy groups were significantly higher (P < 0.050) than those for the hyperlipidemic patients groups. Vitamin D levels for males were significantly higher than females and were significantly higher for healthy than those hyperlipidemic Iraqi patients. These findings showed that vitamin D levels are affected by age, nationality, gender, and health statues and highlight the importance of vitamin D supplementation for groups with low levels particularly old, hijab wearing females, and hyperlipidemic groups.

Vitamin D deficiency and its associated risk factors in children and adolescents in southern Iran

OBJECTIVES

To evaluate prevalence of vitamin D deficiency and its associated factors in southern Iranian children.

DESIGN

Cross-sectional study. Anthropometric and pubertal characteristics were assessed by a trained physician. Physical activity and sun exposure were evaluated using standard questionnaires. Body composition measurements were performed using dual-energy X-ray absorptiometry. Serum Ca, P alkaline phosphatase and 25-hydroxyvitamin D (25(OH)D) were assessed in all children. Statistical analysis was done using the statistical software package IBM SPSS Statistics 18·0.

SUBJECTS

Iranian children (n 477) aged 9-18 years.

SETTING

Fars Province, Iran, 2011.

RESULTS

Of the children, 81·3 % were 25(OH)D deficient. There was no significant difference in 25(OH)D concentration between boys and girls (P=0·3). 25(OH)D concentration was associated with BMI (r=-0·1, P=0·02), pubertal status (r=-0·08, P=0·04) and sun exposure (r=0·10, P=0·04). Fat mass index was associated with 25(OH)D concentration (r=-0·13, P=0·03), but not lean mass index (P=0·86). In multiple regression analysis with adjustment for confounding factors, age and puberty were found to be independently associated with 25(OH)D concentration (P=0·008 and P=0·006); there was a significant correlation between exercise and 25(OH)D concentration after adjustment for either BMI (P=0·01) or fat mass index (P=0·02).

CONCLUSIONS

25(OH)D deficiency is highly prevalent among children in the south of Iran. It is related to insufficient sun exposure, low physical activity, advancing age and pubertal stage. Measures should be taken to improve the health of southern Iranian children in this critical age group by preventing 25(OH)D deficiency.

Vitamin D deficiency and its predictors in a country with thirteen months of sunshine: the case of school children in central Ethiopia

Studies examining vitamin D status among children living in sunny climates indicated that children did not receive adequate vitamin D, however, this has not been looked at among children living in Ethiopia. In this study, we determined vitamin D deficiency and its predictors among school children aged 11–18 years, examining circulating 25-hydroxy vitamin D [25(OH)D]. The school-based cross-sectional study was conducted in schools in Adama Town (n = 89) and in rural Adama (n = 85) for a total sample of 174. Students were randomly selected using multi-stage stratified sampling method from both settings. Socioeconomic status of parents and demographic, anthropometric, sun exposure status and blood 25(OH)D levels were obtained. Vitamin D deficiency, defined as circulating levels of 25(OH)D <50 nmol/L, was found in 42% of the entire study participants. Prevalence of deficiency was significantly higher among students in urban setting compared to rural (61.8% vs 21.2%, respectively, p<0.001). After controlling for potential confounders using multivariable logistic regression model, duration of exposure to sunlight, amount of body part exposed to sunlight, place of residence, maternal education, body fatness, having TV/computer at home and socioeconomic status were significant predictors of vitamin D deficiency. The findings suggest that Vitamin D deficiency was prevalent in healthy school children living both in urban and rural areas of a country with abundant year round sunshine providing UVB, with the prevalence of deficiency being significantly higher among urban school children who were less exposed to sunlight. Behaviour change communication to enhance exposure to ultraviolet light is critical to prevent vitamin D deficiency in tropical country like Ethiopia. Further study is required to assess the deleterious effect of its deficiency on bone mineral homeostasis of growing children in Ethiopia during their most critical period of bone development.

[Calcium intake, serum vitamin D and obesity in children: is there an association?]

OBJECTIVE:

To evaluate the association between calcium intake and serum vitamin D levels and childhood obesity by an integrative review.

DATA SOURCE:

The research was conducted in the databases PubMed/medLine, Science Direct and SciELO with 2001 to 2014 publications. We used the combined terms in English: ''children'' and ''calcium'' or ''children'' and ''vitamin D'' associated with the descriptors: ''obesity'', ''adiposity'' or ''body fat'' for all bases. Cross-sectional and cohort studies, as well as clinical trials, were included. Review articles or those that that have not addressed the association of interest were excluded.

DATA SYNTHESIS:

Eight articles were part of this review, five of which were related to calcium and three to vitamin D. Most studies had a longitudinal design. The analyzed studies found an association between calcium intake and obesity, especially when age and sex were considered. Inverse relationship between serum vitamin D and measures of adiposity in children has been observed and this association was influenced by the sex of the patient and by the seasons of the year.

CONCLUSIONS:

The studies reviewed showed an association between calcium and vitamin D with childhood obesity. Considering the possible protective effect of these micronutrients in relation to childhood obesity, preventive public health actions should be designed, with emphasis on nutritional education.

2015 Guidelines for Osteoporosis in Saudi Arabia: Recommendations from the Saudi Osteoporosis Society

BACKGROUND AND OBJECTIVES

To provide guidelines for medical professionals in Saudi Arabia regarding osteoporosis.

DESIGN AND SETTINGS

A panel of 14 local experts in osteoporosis assembled to provide consensus based on the strength of evidence and expert opinions on osteoporosis treatment.

PATIENTS AND METHODS

The Saudi Osteoporosis Society (SOS) formed a panel of experts who performed an extensive published studies search to formulate recommendations regarding prevention, diagnosis, and treatment of osteoporosis in Saudi Arabia. Both local and international published studies were utilized whenever available.

RESULTS

Dual x-ray absorptiometry (DXA) scanning is still the golden standard for assessing bone mineral density (BMD). In the absence of local, country-specific fracture risk assessment tool (FRAX), the SOS recommends using the USA (White) version of the FRAX tool. All women above 60 years of age should be evaluated for BMD. This is because the panel recognized that osteoporosis and osteoporotic fractures occur at a younger age in Saudi Arabia. Hormone replacement therapy (HRT) is not recommended for treating postmenopausal women with osteoporosis. BMD evaluation should be performed 1-2 years after initiating intervention, and the assessment of bone turnover biomarkers should be performed whenever available to determine the efficacy of intervention.

CONCLUSION

All Saudi women above the age of 60 years must undergo a BMD assessment using DXA. Therapy decisions should be formulated with the use of the USA (White) version of the FRAX tool.

Non-high-density lipoprotein cholesterol and other lipid indices vs elevated glucose risk in Arab adolescents

BACKGROUND

Non-high-density lipoprotein cholesterol (non-HDL-C) has been identified as a significant predictor of various cardiovascular events in adults. Limited studies have been conducted in the pediatric population with diverse results, depending on ethnic origin. None has been conducted in the Arabic adolescent population so far; this study aims to fill this gap.

METHODS

In this cross-sectional study, 1690 Saudi school adolescents (968 boys [mean age 14.8 ± 1.7] and 722 girls [mean age 14.6 ± 1.7]) were recruited. Anthropometrics were obtained. Fasting blood glucose and lipid profiles were quantified routinely. Non-HDL-C was calculated and screening was done for dyslipidemia using cutoffs obtained from the cohort and elevated fasting glucose.

RESULTS

Using the 90th percentile cutoff obtained, the overall prevalence of high non-HDL-C (≥4.26 mmol/L) was 10.1%. Prevalence was slightly higher in girls (10.5%) than boys (9.9%). Non-HDL-C was similar to other lipids in terms of significant associations with anthropometric measures and glucose in both boys and girls. Elevated triglycerides was most predictive of elevated glucose in both girls (odds ratio 2.41; confidence interval 1.43-4.08; P = .001) and boys (odds ratio 2.61; confidence interval 1.70-4.0); P < .001).

CONCLUSION

Non-HDL-C appears to be gender-specific and is cardiometabolically more associated with Saudi boys, despite higher levels in girls. It is inferior compared with triglycerides in assessing elevated glucose risk. Further investigations may provide a more definite value for non-HDL-C use as a biomarker in assessing cardiometabolic risk in the Arab adolescent population.

Polycyclic aromatic hydrocarbon distribution in serum of Saudi children using HPLC-FLD: marker elevations in children with asthma

Diesel exhaust consists of a complex mixture of chemicals which contain known genotoxicants, one of which is polycyclic aromatic hydrocarbons (PAHs) which may be associated with adverse respiratory health outcomes. This study aimed to evaluate the distribution patterns of PAHs (anthracene, naphthalene, fluorene, phenanthrene, cyclopentaphenanthrene, pyrene, fluoranthene, benzanthracene, chrysene, benzo(e)pyrene, benzoacephenanthrylene, and benzo(a)pyrene) in serum collected from asthmatic and healthy control children. PAH serum levels were measured in samples collected from children who lived in 11 different locations in/round Riyadh, Saudi Arabia (Al-yarmouk, Usaibi, Sultana Al-kadema, Omrrojam, Kof, Janoob Dawdmi, Guberah, Arabbuah, Al-mozahemyah, Iskan Al-mazzer, and Al-gharabi) during the period 2010-2011. Our results showed that the highest total mean concentrations of PAH were found in serum samples collected from people who lived in Sultana Aljadhida, Almozahemyah, Guberah, and Omrrojam and were 663.9, 486.17, 412.18, and 258.6 ng ml(-1), respectively. The most prevalent PAHs in serum samples were naphthalene, bezanthracene, benzoacephenanthrylene, phenanthrene, chrysene, and benzo(a)pyrene with a frequency that ranged from 54.5 to 90.9 % positive samples. A close monitoring of PAH pollution is strongly recommended, especially in food and plant samples, because of their high bioaccumulation capacity.

Prevalence of hypovitaminosis D and predictors of vitamin D status in Italian healthy adolescents

Background

Vitamin D plays an important role in health promotion during adolescence. Vitamin D deficiency and insufficiency are common in adolescents worldwide. Few data on vitamin D status and risk factors for hypovitaminosis D in Italian adolescents are currently available.

Methods

25-hydroxyvitamin D (25-OH-D) and parathyroid hormone (PTH) levels were evaluated in 427 Italian healthy adolescents (10.0-21.0 years). We used the following cut-off of 25-OH-D to define vitamin D status: deficiency < 50 nmol/L; insufficiency 50-75 nmol/L; sufficiency ≥ 75 nmol/L. Hypovitaminosis D was defined as 25-OH-D levels < 75.0 nmol/L and severe vitamin D deficiency as 25-OH-D levels < 25.0 nmol/L. We evaluated gender, residence, season of blood withdrawal, ethnicity, weight status, sun exposure, use of sunscreens, outdoor physical activity, and history of fractures as predictors of vitamin D status.

Results

Enrolled adolescents had a median serum 25-OH-D level of 50.0 nmol/L, range 8.1-174.7, with 82.2% having hypovitaminosis D. Vitamin D deficiency and insufficiency were detected in 49.9% and 32.3% of adolescents, respectively. Among those with deficiency, 38 subjects were severely deficient (38/427, 8.9% of the entire sample). Non-white adolescents had a higher prevalence of severe vitamin D deficiency than white subjects (6/17-35.3% vs 32/410-7.8% respectively, p = 0.002). Logistic regression showed increased risk of hypovitaminosis D as follows: blood withdrawal taken in winter-spring (Odds ratio (OR) 5.64) compared to summer-fall period; overweight-obese adolescents (OR 3.89) compared to subjects with normal body mass index (BMI); low sun exposure (OR 5.94) compared to moderate-good exposure and regular use of sunscreens (OR 5.89) compared to non regular use. Adolescents who performed < 3 hours/week of outdoor exercise had higher prevalence of hypovitaminosis D. Gender, residence, and history of fractures were not associated with vitamin D status. Serum 25-OH-D levels were inversely related to PTH (r = -0.387, p < 0.0001) and BMI-SDS (r = -0.141, p = 0.007). 44/427 (10.3%) adolescents showed secondary hyperparathyroidism.

Conclusions

Italian adolescents have high prevalence of vitamin D deficiency and insufficiency. Pediatricians should tackle predictors of vitamin D status, favoring a healthier lifestyle and promoting supplementation in the groups at higher risk of hypovitaminosis D.

Stress and cardiometabolic manifestations among Saudi students entering universities: a cross-sectional observational study

Background

In this observational study, we aimed to see whether transition in Saudi students entering university life could be a breeding stage for cardiometabolic risk factor emergence and clustering.

Methods

A total of 1878 apparently healthy Saudi students of the Preparatory Year, King Saud University, Riyadh, KSA (1112 men and 766 women) spanning 2 academic years were included. They were divided into 2 groups based on the validated perceived stress test (PST). Anthropometrics were obtained and fasting blood samples were collected for measurement of fasting blood glucose and a lipid profile.

Results

PST score (>27) considered indicative of stress was noted in 44.4% of students. The prevalence of this score was higher in women than in men (49.7% versus 40.7%). The prevalence of obesity, hypertension and dyslipidemia was significantly higher in men than women (p < 0.01), and this was even more apparent among stressed men, who had a significantly higher prevalence of all the above cardiometabolic factors than the non-stressed ones (p < 0.01).

Conclusion

Perceived stress is alarmingly high among Saudi students entering universities. This study sheds light on the social responsibility of universities in promoting a healthy lifestyle, particularly in this age group, when exposure to different kinds of stressors may result in body weight and metabolic changes.

The association of vitamin D status with cardiometabolic risk factors, obesity and puberty in children

Low serum 25-hydroxyvitamin D3 (25(OH)D) levels have been associated with insulin resistance and cardiovascular diseases. The influences of gender, puberty and adiposity on vitamin D status and the relationship between 25(OH)D and cardiometabolic risk factors in obese and non-obese children were studied. A retrospective analysis was carried out on 168 Turkish children during late winter. Age, gender, puberty, body mass index (BMI), 25(OH)D levels and cardiometabolic risk factors including lipid profiles, high-sensitivity C-reactive protein and insulin resistance index calculated by homeostasis model assessment (HOMA-IR) were evaluated. The median age of the study population was 11 (4-16) years, and 102 children (60.7 %) were prepubertal. Overall, 98.2 % of patients had 25(OH)D levels lower than 20 ng/mL (median 10.0 (4.0-21.3) ng/mL). The 25(OH)D levels did not correlate with BMI. However, an inverse correlation was seen between serum 25(OH)D and HOMA-IR (rho = -0.656, p = 0.006) and insulin (rho = -0.715, p = 0.002) in pubertal obese subjects. Female gender and puberty were all negatively associated with 25(OH)D.

CONCLUSION

The association between vitamin D status and BMI is complex, and it does not seem to be altered by mild obesity. In addition, potential influence of puberty should be kept in mind while assessing the relationship between serum 25(OH)D and cardiometabolic risk factors.

Food allergy: the perspectives of prevention using vitamin D

PURPOSE OF REVIEW

We reviewed the scientific publications in the last 2 years on the connections between vitamin D and food allergy, and endeavor to focus on the possible indications for supplementation in order to prevent allergies.

RECENT FINDINGS

Ecological studies have suggested a possible relationship between sun exposure and atopic diseases such as asthma, atopic dermatitis and anaphylaxis. However, no direct evaluation of vitamin D status has been performed. Recent studies evaluating the relationship with vitamin D levels at birth or during pregnancy have shown conflicting results with the lower levels of vitamin D associated with eczema, the higher with increased food allergy prevalence.

SUMMARY

Although the role of vitamin D in extraskeletal function is certainly intriguing and must not be underestimated, at the moment there is a lack of consistent data addressing the topic of vitamin D supplementation in the prevention of food allergies. However, in light of the vast amount of literature regarding the mechanisms connected with atopic diseases, an evaluation of serum levels of vitamin D and eventually supplementation must be considered as a further opportunity to understand and treat atopic diseases. In this regard, well designed trials on vitamin D supplementation to prevent food allergies are urgently needed.

Independent association between air pollutants and vitamin D deficiency in young children in Isfahan, Iran

OBJECTIVES

To determine the association between air pollution and vitamin D status in young children living in a sunny region.

METHODS

This cross-sectional study of 100 children aged 4-10 years in Isfahan was conducted during 2011-2012. This industrial city has an arid climate and is the second most air-polluted city in Iran. Children were selected by random cluster sampling from various areas with different levels of air pollution. The air quality index (AQI) was recorded and demographic variables, dietary habits and levels of physical activity were determined by validated questionnaires. Serum concentrations of 25-hydroxyvitamin D [25(OH)D], calcium, phosphate, alkaline phosphatase and parathyroid hormone were measured. The P for trend for median (interquartile range) of variables was assessed across the AQI quartiles. The associations between AQI and biochemical values were assessed by multiple linear regression after adjustment for age, gender, BMI, diet and pattern of physical activity.

RESULTS

Ninety-seven children (46.4% boys) completed the study. The median (interquartile range, IQR) of serum 25(OH) D was 37.4 (22.5, 81.6) nmol/L. Median dietary vitamin D intake was 11.7 μg/day, i.e. 78% of the required daily amount. Vitamin D deficiency and insufficiency were detected in 37.9% and 46.3% of children, respectively. Median (IQR) exposure to ultraviolet B radiation in the AQI Quartile 4 area was significantly lower than in the Quartile 1 area [0.36 (0.35-0.38) watts per square metre (W/m(2)) vs 0.41 (0.39-0.44) W/m(2), respectively, P = 0.04]. Likewise, the corresponding figure for serum 25(OH)D was 35.2 (22.5-45.2) vs 52.7 (44.9-81.6) nmol/L, respectively, P = 0.04. AQI was inversely associated with serum 25(OH)D, which remained significant after adjustment for the above-mentioned confounding factors (β = 0.61, P = 0.01).

CONCLUSION

The independent inverse association of AQI with 25(OH)D explains the high prevalence of vitamin D deficiency in children in Isfahan. Dietary intake of vitamin D was not sufficiently low to explain the very low level of serum 25(OH)D. In regions with plenty of sunlight, air pollution should be considered to be a factor in the causation of hypovitaminosis D.

Vitamin D status and predictors of hypovitaminosis D in Italian children and adolescents: a cross-sectional study

Hypovitaminosis D affects children and adolescents all around the world. Italian data on vitamin D status and risk factors for hypovitaminosis D during pediatric age are lacking. Six hundred fifty-two children and adolescents (range 2.0-21.0 years) living in the northwestern area of Tuscany were recruited at the Department of Pediatrics, University Hospital Pisa. None of them had received vitamin D supplementation in the previous 12 months. 25-hydroxyvitamin D (25-OH-D) and parathyroid hormone (PTH) levels were analyzed in all subjects. Severe vitamin D deficiency was defined as serum levels of 25-OH-D<25.0 nmol/L (10.0 ng/mL) and vitamin D deficiency a<50.0 nmol/L (20.0 ng/mL). Serum 25-OH-D levels of 50.0-74.9 nmol/L (20.0-29.9 ng/mL) indicated vitamin D insufficiency, whereas 25-OH-D levels ≥ 75.0 nmol/L (30.0 ng/mL) were considered sufficient. Hypovitaminosis D was defined as 25-OH-D levels<75.0 nmol/L (30.0 ng/mL). The median serum 25-OH-D level was 51.8 nmol/L, range 6.7-174.7 (20.7 ng/mL, range 2.7-70.0), with a prevalence of vitamin D deficiency, insufficiency, and sufficiency of 45.9, 33.6, and 20.5 %, respectively. The prevalence of severe vitamin D deficiency was 9.5 %. Adolescents had lower median 25-OH-D levels (49.8 nmol/L, range 8.1-174.7; 20.0 ng/mL, range 3.2-70.0) than children (55.6 nmol/L, range 6.8-154.6; 22.3 ng/mL, range 2.7-61.9, p=0.006). Non-white individuals (n=37) had median serum 25-OH-D levels in the range of deficiency (28.2 nmol/L, range 8.1-86.2; 11.3 ng/mL, range 3.2-34.5), with 36/37 having hypovitaminosis D. Logistic regression showed significant increased risk of hypovitaminosis D in the following: blood samples taken in winter (odds ratio (OR) 27.20), spring (OR 26.44), and fall (OR 8.27) compared to summer; overweight (OR 5.02) and obese (OR 5.36) subjects compared to individuals with normal BMI; low sun exposure (OR 8.64) compared to good exposure, and regular use of sunscreens (OR 7.06) compared to non-regular use. Gender and place of residence were not associated with vitamin D status. The 25-OH-D levels were inversely related to the PTH levels (r=-0.395, p<0.0001). Sixty-three out of the 652 (9.7 %) subjects showed secondary hyperparathyroidism.

CONCLUSION

Italian children and adolescents who were not receiving vitamin D supplementation had high prevalence of hypovitaminosis D. Careful identification of factors affecting vitamin D status is advisable to promptly start vitamin D supplementation in children and adolescents.

Decreased circulating 25-(OH) Vitamin D concentrations in obese female children and adolescents: positive associations with Retinol Binding Protein-4 and Neutrophil Gelatinase-associated Lipocalin

OBJECTIVE

Hypovitaminosis D has been associated with adult as well as childhood obesity. Retinol-binding-protein-4 (RBP-4) and Neutrophil Gelatinase-associated Lipocalin (NGAL) are altered in obese individuals. The aim of this study was to examine circulating 25-(OH) Vitamin D (25-(OH) D) concentrations according to BMI and its associations with RBP-4 and NGAL in female children and adolescents.

DESIGN

Seventy-nine (79) children, aged 8-16 years, were studied and divided into four groups: 19 control (BMI z-score range -2.15 - 1.24), 20 overweight (1.34 - 2.49), 20 obese (2.50 - 2.87) and 20 ultra-obese (3 - 4.37). Patients were derived from a Pediatric Obesity Clinic. Plasma 25-(OH) D, RBP-4 and NGAL concentrations were measured with specific assays.

RESULTS

Plasma 25-(OH) D concentrations were decreased significantly in the ultra-obese (p=0.005) and marginally in the obese group (p=0.05) compared to the control group. In the entire BMI range, Spearman correlations revealed strong positive associations between 25-(OH) D and RBP-4 (r=0.349, p=0.002) and between 25-(OH) D and NGAL (r=0.338, p=0.003).

CONCLUSIONS

25-(OH) D is deficient in a clinical population of obese female children and adolescents, whereas in the entire BMI range 25-(OH) D is associated with RBP4 and NGAL concentrations. Longitudinal studies are needed to reveal the role of these associations in metabolic alterations related to childhood and adolescent obesity and associated metabolic morbidities.

Effect of physical activity and sun exposure on vitamin D status of Saudi children and adolescents

Background

Accumulating evidence suggests an increased prevalence of vitamin D deficiency in the Middle East. In this context, we aimed to determine whether the prevalence of vitamin D deficiency is related to degree of physical activity and sun exposure among apparently healthy Saudi children and adolescents, a little studied population.

Methods

A total of 331 Saudi children aged 6–17 years (153 boys and 178 girls) were included in this cross sectional study. Levels of physical activity and sun exposure were determined using a standard questionnaire. Anthropometry, serum calcium and 25-(OH) vitamin D were analyzed.

Results

All subjects were vitamin D deficient, the majority being moderately deficient (71.6%). Age was the single most significant predictor affecting 25 (OH) Vitamin D levels, explaining 21% of the variance perceived (p = 1.68 x 10^-14). Age-matched comparisons revealed that for groups having the same amount of sun exposure, those with moderate or are physically active will have higher levels of vitamin D status, though levels in across groups remained deficient.

Conclusion

Vitamin D deficiency is common among Saudi children and adolescents, and is influenced by both sun exposure and physical activity. Promotion of an active outdoor lifestyle among Saudi children in both homes and schools may counteract the vitamin D deficiency epidemic in this vulnerable population. Vitamin D supplementation is suggested in all groups, including those with the highest sun exposure and physical activity.

Macronutrient intake influences the effect of 25-hydroxy-vitamin d status on metabolic syndrome outcomes in african american girls

The objectives were to determine the effect of macronutrient modification on vitamin D status and if change in 25-hydroxy-vitamin D concentration influences components of metabolic syndrome in obese African American girls. Methods. Five-week intervention using reduced CHO (43% carbohydrate; 27% fat: SPEC) versus standard CHO (55% carbohydrate; 40% fat: STAN) eucaloric diet. Subjects were 28 obese African American females, aged 9-14 years. Dual energy X-ray absorptiometry and meal test were performed at baseline and five weeks. Results. Approximately 30% of girls had metabolic syndrome. Serum 25OHD increased in both groups at five weeks [STAN: 20.3 ± 1.1 to 22.4 ± 1.1 (P < 0.05) versus SPEC: 16.1 ± 1.0 to 16.8 ± 1.0 (P = 0.05)]. The STAN group, increased 25OHD concentration over five weeks (P < 0.05), which was positively related to triglycerides (P < 0.001) and inversely associated with total cholesterol (P < 0.001) and LDL (P < 0.001). The SPEC group, had increase in 25OHD (P = 0.05), which was positively related to fasting insulin (P < 0.001) and insulin sensitivity while inversely associated with fasting glucose (P < 0.05). The contribution of vitamin D status to metabolic syndrome parameters differs according to macronutrient intake. Improvement in 25OHD may improve fasting glucose, insulin sensitivity, and LDL; however, macronutrient intake warrants consideration.

Vitamin D deficiency in girls from South Brazil: a cross-sectional study on prevalence and association with vitamin D receptor gene variants

BACKGROUND

Vitamin D deficiency has been associated with a multitude of disorders including diabetes, defective insulin secretion as well as rickets and poor bone health. Vitamin D is also a concern during childhood and adolescence and has been reported in girls from South Brazil. We determined the prevalence of vitamin D deficiency in girls from South Brazil and investigated whether the genotypic distribution of the BsmI, ApaI and TaqI polymorphisms of the VDR gene and their haplotypes were associated with vitamin D levels.

METHODS

Cross-sectional study including 234 apparently healthy girls aged 7 to 18 years. Height and weight were measured for calculation of body mass index (BMI) percentiles for age. Plasma levels of 25-hydroxyvitamin D [25(OH)D] were assessed. Participants were genotyped for ApaI (rs7975232), TaqI (rs731236), and BsmI (rs1544410) SNPs.

RESULTS

The median and interquartile range (25-75%) of BMI percentile was 62.0 (33.3 - 84.9). The frequency of overweight/obesity was 24.9%. Circulating levels of 25(OH)D (≥ 30 ng/mL) were adequate in 9.4%; insufficient in 54.3% (20-29 ng/mL); and deficient in 36.3% (< 20 ng/mL). Genotype frequencies were GG = 47.0%, GA = 41.5%, and AA = 11.5% for BsmI; GG = 16.7%, GT = 52.6%, and TT = 30.8% for ApaI; TT = 46.2%, TC = 44.9% and CC = 9.0% for TaqI. Genotypes with no gene variance (ancestral wild genotype) of BsmI (GG vs. GA + AA, two-tailed Student's t-test p < 0.001), ApaI (GG vs. GT + TT, two-tailed Student's t-test p = 0.031) and TaqI (TT vs. TC + CC, two-tailed Student's t-test p = 0.005) SNPs and the GGT haplotype (two-tailed Student's t-test p = 0.036) were significantly associated with lower 25(OH)D levels.

CONCLUSIONS

25-hydroxyvitamin D deficiency and insufficiency were highly prevalent in this sample. The BsmI, ApaI and TaqI wild variants of the VDR gene, as well as the GGT haplotype, were associated with lower vitamin D levels, suggesting that VDR gene polymorphisms could be linked to higher susceptibility to vitamin D deficiency in a sub-population of children and adolescents.